ITM 360 Spring 2013Exam 2 with answers

1. What is a set of agreed-upon instructions designed to allow computers to communicate to each other across a network connection?a) protocolb) checksumc) technologyd) port

Answer: aDifficulty: EasySection Reference: Protocol SuitesExplanation: In computer networking, a protocol is a set of agreed-upon instructions designed to allow computers to communicate to each other across a network connection. Many protocols are used in networking because many different tasks need to be done to allow computers to communicate with each other.

4. Which core protocol used on the Internet moves data packets from one location on a packet-switched network to another location based on a logical address?a) IPb) TCPc) UDPd) ICMP

Answer: aDifficulty: MediumSection Reference: Internet Layer ProtocolsExplanation: The TCP/IP model’s Internet layer is the first layer to have TCP/IP protocol suite–specific protocols. The Internet Protocol (IP) is the most important protocol on this layer and is one of the two protocols used to name the TCP/IP protocol suite.

5. What mathematical function is performed on data to ensure that it has not been changed or corrupted?a) corrupt aliasb) Arp-ingc) checksumd) MAC

Answer: cDifficulty: EasySection Reference: IPExplanation: Before data is sent, a mathematical calculation is done on the data and is sent with the data. When the data is received, the same mathematical calculation is done and the two checksum calculations are compared. If they are the same, the data packet has not been changed or corrupted.

6. Which protocol translates an IP address into a MAC address?a) ARPb) ICMPc) DNSd) WINS

Answer: aDifficulty: MediumSection Reference: ARPExplanation: In network addressing—when a packet is passed along a network via routers—the MAC address is actually changed at each hop so that the data frame can move on to the next hop in its

journey. The Address Resolution Protocol (ARP)is responsible for changing the MAC address. Part of ARP’s job is to determine what the MAC address is for the next hop and then adjust the frame accordingly so that the frame can be moved to the next hop.

7. Which protocol is used to send messages about the network when a route goes bad?a) ARPb) ICMPc) DNSd) WINS

Answer: bDifficulty: MediumSection Reference: ICMPExplanation: The Internet Control Message Protocol (ICMP) is used mainly by a computer’s operating system to send messages about the network. When an error occurs in the IP packet, a service is unreachable or down, a host is not found, or a router is down, among other situations, an ICMP message is sent.

8. What command is used to test IP connectivity between two hosts?a) pingb) arpc) nslookupd) netsh

Answer: aDifficulty: EasySection Reference: PingExplanation: Ping is a network administration utility that is used to test connectivity to specific nodes on a network and to measure the round-trip time it takes for a packet to get to a specific destination and back.

10. What command tests connectivity between two hosts while showing each hop between the two hosts?a) pingb) tracertc) arpd) loopback

Answer: bDifficulty: EasySection Reference: Trace RouteExplanation: The traceroute/tracert utility is used to report back each hop along a route to a specific IP destination.

12. What mechanism is used to send one set of packets to multiple hosts at the same time?a) ICMPb) IGMPc) multicastingd) looping

Answer: cDifficulty: EasySection Reference: IGMPExplanation: IP multicasting is basically an IP host’s capability to send a datagram or data packet to all IP hosts within a host group. A host group consists of all the IP computers currently connected to a particular IP multicast host that are set to receive the same transmission from that host. These host groups can be set to contain 0 or more hosts.

13. What is used to determine which upper-layer protocols, services, and processors each data segment is intended for?a) checksumb) portc) MAC addressd) IP address

Answer: bDifficulty: EasySection Reference: PortsExplanation: Protocols on the Transport layer have port addresses, also known as ports. These ports are used to determine which upper-layer protocols, services, and processes each data segment is intended for. Port addresses ensure that the correct protocol, service, or process can get the data intended for it. The two main protocols on the Transport layer, UDP and TCP, both use ports.

14. What type of port ranges from 0 to 1023?a) well-known portsb) registered portsc) dynamic portsd) private ports

Answer: aDifficulty: EasySection Reference: PortsExplanation: The first group is called the well-known ports. Port numbers in this group range from 0–1023. Well-known ports can be assigned only by the Internet Assigned Numbers Authority (IANA). The ports in this range, according to IANA, can be used only by the system or root processes and by programs executed by privileged users.

17. What port does HTTP use by default?a) 21b) 80c) 67d) 443

Answer: bDifficulty: EasySection Reference: PortsExplanation: Hyper-Text Transfer Protocol (HTTP) uses TCP port 80 to display web pages via a browser.

18. What protocol uses TCP port 25?a) FTPb) SNMPc) SMTPd) HTTP

21. Which connection-oriented protocol ensures that data gets its final destination?a) TCPb) SNMPc) UDPd) ICMP

Answer: aDifficulty: EasySection Reference: TCP

Explanation: TCP focuses on the two end devices, whereas IP focuses on getting the network packet from one device to the next toward its ultimate destination.

22. Which connectionless transport protocol does not guarantee reliable delivery?a) TCPb) HTTPc) UDPd) FTP

Answer: cDifficulty: MediumSection Reference: UDPExplanation: User Datagram Protocol (UDP) is the connectionless counterpart of TCP. It does not guarantee reliable delivery and is used primarily to give other protocols, such as IP, access to datagram services like port numbers. Due to the limited functionality provided by UDP, the header is correspondingly much smaller and less complex.

23. What protocol is used to assign IP addresses automatically to a host?a) DHCPb) DNSc) WINSd) ICMP

Answer: aDifficulty: easySection Reference: DHCP and BOOTPExplanation: DHCP was first introduced in RFC 1541 in 1993 and was intended as a replacement for the older and less wieldy BOOTP. DHCP assigns IP addresses and IP configurations automatically for the host.

25. Which protocol is used to resolve host names to IP addresses?a) DNSb) WINSc) DHCPd) SMB

Answer: aDifficulty: EasySection Reference: DNSExplanation: Domain Name System (DNS) makes it possible for us to use the Internet the way we do. DNS is the protocol that converts all those URLs we can easily remember to IP addresses that the Internet can use.

27. When a DNS client needs to resolve a host name to an IP address, where will it first check?a) LMHOST fileb) nearest DNS serverc) its own DNS cached) designated DNS server

Answer: cDifficulty: MediumSection Reference: DNSExplanation: When you open your web browser and put in a URL, the browser checks the local web cache to see if the IP address of the entered URL can be found. If it cannot be found, your computer sends a query to your ISP’s DNS server asking it for the URL’s IP address.

28. What protocol is used to transport and display web pages using a browser?a) DNSb) SMBc) HTTPd) WINS

Answer: cDifficulty: EasySection Reference: HTTPExplanation: Hyper-Text Transport Protocol (HTTP) is used to transport Hyper-Text Markup Language (HTML) documents, otherwise known as web pages, over the Internet. HTTP can also be used to retrieve graphics, images, and other types of media and it can be used with email.

31. What protocol is used to send and manipulate files over a TCP/IP network?a) FTPb) HTTPSc) WINSd) ICQ

Answer: aDifficulty: EasySection Reference: FTPExplanation: The most commonly used current version of File Transfer Protocol (FTP) was first introduced in 1985 in RFC 959. However, FTP in its original form was introduced in 1971 using RFC 114.

34. What protocol is used to provide bi-directional interactive command-line access to either a remote or local host?a) RTPb) TELNETc) SIPd) HTTP

Answer: bDifficulty: EasySection Reference: TELNETExplanation: TELNET, short for TErminaL NETwork, is used to provide bi-directional interactive command-line access to either a remote or local host. TELNET was first introduced in 1969 in RFC 15. In 1983, TELNET was extended in RFC 854. TELNET client software can be found for pretty much every computer platform out there.

36. Which protocol is used to retrieve emails?a) POP3b) DNSc) SIPd) VoIP

Answer: aDifficulty: EasySection Reference: POP3Explanation: Post Office Protocol (POP) is used to connect to an email server and retrieve any emails on that server before closing the connection. When POP3 retrieves emails, it can either leave copies on the server, or delete the emails from the server after it downloads them to the client system.

37. What routing type is manually defined?a) static routingb) dynamic routing

c) metric routingd) exterior routing

Answer: aDifficulty: EasySection Reference: Static vs. Dynamic RoutingExplanation: The most basic way of building routing tables is to manually create one in a router. As new routes are needed on a network or old routes change, the routing tables must be manually changed or updated on the affected routers. This process is called static routing, which is time-consuming and prone to errors.

38. What measurement is used to choose the best route to a specific location?a) dynamicsb) SIPsc) metricsd) checksum

Answer: cDifficulty: MediumSection Reference: Routing MetricsExplanation: The purpose of any routing protocol is to compile a table listing all routes known to it so that IP can use the table to find the best route to a specific location. The measurements used by a routing protocol to determine the best routes available to it are called metrics.

39. What represents the number of routers it takes to get from one destination to another?a) hopsb) TTLsc) lengthsd) latency

Answer: aDifficulty: MediumSection Reference: Understanding Routing Tables and How They Apply to Path SelectionExplanation: Within a routing table database are several information fields. The three most common of these fields are the network ID of the destination network, the cost of path the packet will need to take to get to the destination network, and the next hop. The cost refers to the network cost (not money cost) of getting to the destination network, which is based on available bandwidth, speed and other factors..

40. Which type of routing protocol are RIP and IGRP?a) distance vector routing protocolb) link state routing protocolsc) hybrid routing protocolsd) placement routing protocols

Answer: aDifficulty: MediumSection Reference: Distance Vector Routing ProtocolsExplanation: The simplest type of routing protocol is a distance vector routing protocol. Some examples of distance vector routing protocols are RIP, RIPv2, and IGRP. In a distance vector routing protocol, each router periodically sends an update of its routing table to all routers directly connected to it. In this way, periodically the entire network of routers gets updated. The time it takes for this update to take place is called convergence.

3. On which OSI layer does the network interface card work?a) Physicalb) Network

c) Transportd) Application

Answer: aDifficulty: MediumSection Reference: Medium and MediaExplanation: A NIC is required to work on both the Data-Link and Physical layers of the OSI model. The NIC acts as translator between the software in the upper layers of the OSI model and the physical components of the media.

4. What is the physical address assigned to a NIC?a) MAC addressb) IP addressc) DNS addressd) WINS address

Answer: aDifficulty: MediumSection Reference: AddressingExplanation: The physical address, also known as the MAC address, assigned to a NIC by its manufacturer is 48 bits long. Because of the way this address is divided up into two 24 bit parts, each manufacturer has only 16 million or so unique addresses they can use before the manufacturer has begun reusing physical addresses.

5. You are given the following address: 00-90-4B-AD-2A-ACWhat type of address is this?a) MAC addressb) IP addressc) DNS addressd) WINS address

Answer: aDifficulty: EasySection Reference: AddressingExplanation: The physical address, also known as MAC address, assigned to a NIC by its manufacturer is 48 bits long. Because of the way this address is divided up into two 24-bit parts, each manufacturer has only 16 million or so unique addresses to use before the manufacturer has to start reusing physical addresses.

6. What networking device is used to modulate an analog signal in such a way that it can encode digital information?a) modemb) NICc) Codecd) radar

Answer: aDifficulty: EasySection Reference: ModemsExplanation: The word modem is short for modulator/demodulator. A modem is a networking device that is used to modulate an analog signal in such a way that it can encode digital information or to demodulate the encoded signal so that it can be decoded back into something a computer can read. Any device used to encode digital information onto analog communication links, regardless of throughput, can rightfully be called a modem.

7. What device converts one type of media to another type?

a) protocol analyzerb) media converterc) host converterd) transceiver

Answer: bDifficulty: EasySection Reference: Media ConvertersExplanation: Media converters are used to convert one type of media to another type. Such devices are used to convert coaxial to twisted pair or fiber to copper. These types of devices are important for allowing two different types of technologies on the same network.

8. What is used to repeat a signal it receives and rebroadcast it?a) transceiverb) repeaterc) modemd) converter

Answer: bDifficulty: EasySection Reference: Repeaters and HubsExplanation: A repeater is a device that repeats a signal it receives in order to rebroadcast it, thus extending the range of a particular cable run. A repeater is always active and requires a power source of some sort. It has one cable coming in and one going out.

9. What is a multiport repeater?a) hubb) routerc) bridged) modem

Answer: aDifficulty: EasySection Reference: Repeaters and HubsExplanation: Hubs work as though they are the bus of a larger network. When a computer connected to one port of a hub want to connect to a computer connected to a different port on a hub, it has to broadcast the signal to all devices connected to that hub. In this way, a hub acts as a bus. As a signal comes into a hub, it is regenerated or repeated and sent to its destination.

10. What type of hub does not amplify or resend a signal?a) intelligent hubb) active hubc) passive hubd) collision hub

Answer: cDifficulty: MediumSection Reference: Repeaters and HubsExplanation: A passive hub is really nothing more than a cable splitter. If you have seen old cable TV connections where a coaxial cable is connected to a cable splitter and two or more cables come out, you have seen what is essentially a passive hub. These types of devices are not used very commonly in data networks.

13. In what type of network segment do computers have the possibility of having their signals collide with each other?a) intelligent domain

b) clashing domainc) interference domaind) collision domain

Answer: dDifficulty: MediumSection Reference: Explanation: A network segment where computers have the possibility of having their signals collide with each other is called a collision domain. If too many computers are on a single collision domain, a network can reach a point where it has so many collisions, no computers can actually communicate with each other. Therefore, the goal of a hub-based network is to have as few computers as possible on a single collision domain.

14. What connects two network segments together, yet only forwards packets based on MAC addresses from one segment to another segment only when needed?a) bridgeb) hubc) routerd) gateway

Answer: aDifficulty: MediumSection Reference: BridgesExplanation: Bridges are intended to break up networks into smaller sections; as a result, they are more intelligent than your average hub. Because bridges work on the Data-Link layer of the OSI model, they can read and make sense of MAC addresses. Based on these MAC or Physical addresses, a bridge can determine whether a frame is allowed to pass through to the other side of the bridge.

15. On what OSI layer does a switch operate?a) Physicalb) Data-Linkc) Networkd) Transport

Answer: bDifficulty: MediumSection Reference: SwitchesExplanation: Switches, like bridges, work primarily on the Data-Link layer of the OSI model.

17. What device has each port as its own collision domain?a) repeaterb) active hubc) passive hubd) switch

Answer: dDifficulty: MediumSection Reference: Basic SwitchExplanation: A basic switch can be referred to as a multiport bridge because like a bridge, it can separate a network out into multiple collision domains.

19. What is referred to as a group of hosts in the Data-Link layer that share a common set of communications requirements and can be isolated from other groups?a) LANb) MANc) VLAN

d) WAN

Answer: cDifficulty: MediumSection Reference: VLANsExplanation: In its most basic form, a VLAN (short for Virtual LAN) enables you to break up a much larger network into smaller networks within the Data-Link layer of the OSI model. In other words, a VLAN refers to a group of hosts that share a common set of communications requirements whether or not they are attached to the same device.

21. What is used to identify VLANs?a) IP addressb) network numbersc) IP prefixd) VLAN numbers

Answer: dDifficulty: EasySection Reference: VLANsExplanation: If you want to create multiple VLANs, you define which ports are assigned to each VLAN, and then each VLAN is assigned a VLAN number.

25. When you use port authentication, what is used to limit access to the network?a) VLAN numberb) IP addressc) Passwordsd) MAC addresses

Answer: dDifficulty: MediumSection Reference: Port AuthenticationExplanation: Port authentication provides security to the entire network because it limits access via a particular port to pre-authorized MAC addresses.

26. What protocol do multiple switches on the same network use to ensure that an infinite loop is not created?a) trunkingb) SIPc) VLANd) STP

Answer: dDifficulty: MediumSection Reference: Port MirroringExplanation: Spanning Tree Protocol (STP) is used when multiple switches are implemented on the same network. As a Data-Link layer protocol, STP is used primarily to prevent endless loops from developing on switch-based LANs. The protocol gets its name from a mathematical algorithm called “spanning tree,” which takes a group of points and connects them all together without allowing any loops to form.

27. What is used to convert digital signals from one frame format to another, specifically to convert Frame Relay into Ethernet signals?a) switchb) hubc) CSU/DSUd) bridge

Answer: cDifficulty: MediumSection Reference: CSU/DSUExplanation: A Channel Service Unit/Data Service Unit (CSU/DSU) converts a digital signal from one frame format to another. Most commonly, it is used to convert Frame Relay or T-1 signals into Ethernet signals.

29. At what OSI layer do routers operate?a) Physicalb) Data-linkc) Networkd) Transport

Answer: cDifficulty: MediumSection Reference: Routers and FirewallsExplanation: Routers are networking devices used to move packets around a larger network. To do this, they have to be very intelligent and able to read data packets to know where they are intended to go and where they have come from. Because routers are meant to relay based on IP addresses, they work on the Network layer.

30. What is used to protect a network from unauthorized access?a) routerb) firewallc) switchd) CSU/DSU

Answer: bDifficulty: EasySection Reference: Routers and FirewallsExplanation: The firewall that is mentioned here, is not the “firewall” that you load onto your computer to protect it from internet attacks. A firewall is a networking device whose purpose is to prevent unauthorized packets from getting into your network. It is also used as the first line of defense between a private network and the Internet.

33. Where would you place a web server that will be accessed from the Internet?a) DMZb) Internetc) intranetd) VLAN

Answer: aDifficulty: MediumSection Reference: Routers and FirewallsExplanation: Because a web server that needs to be accessed needs to have some security but should be isolated from the internal network, you should place the web server on the DMZ.

35. What type of server acts as an intermediary between a client and other servers?a) SMB serverb) port serverc) proxy serverd) DNS server

Answer: cDifficulty: HardSection Reference: Proxy Servers

Explanation: Proxy servers act as intermediaries between a client and other servers. They can fulfill many roles and can be used for many different jobs.

37. What is used to monitor the activity of a network and notify network administrators when it identifies something as suspicious?a) IDSb) PoEc) STPd) VLAN

Answer: aDifficulty: MediumSection Reference: Intrusion Detection Systems (IDS) and Intrusion Protection Systems (IPS)Explanation: Intrusion Detection Systems (IDS) and Intrusion Prevention Systems (IPS) are related technologies. An IDS usually sits inside a network and monitors the network’s activities. When something suspicious is noted, the IDS then notifies network administrators so that they can take steps to stop the suspect activity. Because an IDS only monitors activity, it is considered passive.

3. Which Ethernet frame type supports TCP/IP?a) Ethernet IIb) Ethernet 802.3c) Novell Ethernetd) Ethernet SNAP

Answer: aDifficulty: Medium Section Reference: Ethernet FramesExplanation: The most widely used Ethernet frame type is Ethernet II or Ethernet DIX. It is so widely used because the Internet Protocol (IP) can use it directly.

4. What type of access method does Ethernet use?a) CSMA/CAb) CSMA/CDc) token passingd) polling

Answer: bDifficulty: MediumSection Reference: Ethernet Communications MethodsExplanation: Carrier Sensing Media Access/Collision Detection (CSMA/CD) is the primary method that Ethernet uses to access wired LANs. Ethernet uses a different method to access wireless LANs.

5. What type of access method is used in wireless networks?a) CSMA/CAb) CSMA/CDc) token passingd) polling

Answer: aDifficulty: MediumSection Reference: Ethernet Communications MethodsExplanation: Like CSMA/CD, Carrier Sensing Media Access/Collision Avoidance (CSMA/CA) is a method used by Ethernet to access a local area network. Where CSMA/CD is most commonly used for wired networks, CSMA/CA is most commonly used for wireless networks.

6. What happens when two computers broadcast at the same time on the network, causing both sets of data to be garbled?a) crashb) EMIc) EFId) collision

Answer: dDifficulty: EasySection Reference: Ethernet Communications MethodsExplanation: When two different computers need to send data at the same time, they will listen to the network. If neither computer hears any activity on the network, they both will conclude that they are clear to send data at that time. As a result, both computers end up sending data packets simultaneously; however, because only one data packet can be on the network cable at one time, a collision occurs. The collision results in a slight power spike on the network as well as destruction of the data in the two packets.

7. When a collision occurs, what do the two sending nodes do?a) They both wait a random amount of time and try again.b) The computer on the right goes first.c) The nearest computer goes first.d) They immediately try again.

Answer: aDifficulty: MediumSection Reference: Ethernet Communications MethodsExplanation: When computers on the network segment “hear” a collision on the network, they all immediately activate something called a hold-down timer. This timer is effectively a clock that activates in each NIC on the network and starts counting down from a randomly set point of time. While the clock on a particular NIC is counting down, it cannot send any packets. As each computer on the network segment finishes its random countdown, it can begin listening to the network again to find an open point where it can begin to send its data packet.

9. What media type can carry multiple data signals at the same time?a) basebandb) broadbandc) singlebandd) multiband

Answer: bDifficulty: EasySection Reference: Baseband Ethernet TechnologiesExplanation: Baseband means is that a cable can carry only one signal one way at one time. In the case of most modern Ethernet cables, this means that there is one line for sending signals and another line for receiving signals inside an Ethernet cable.

11. Ethernet is considered ___________.a) basebandb) broadbandc) singlebandd) multiband

Answer: aDifficulty: EasySection Reference: Baseband Ethernet Technologies

Explanation: Ethernet is what is called a baseband technology. Most modern Ethernet cables have one line for sending signals and another line for receiving signals.

12. Today, what type of cable is the most common for Ethernet?a) coaxialb) STPc) UTPd) fiber

Answer: cDifficulty: Easy Section Reference: Baseband Ethernet TechnologiesExplanation: Today, virtually all Ethernet cabling is done with either UTP or fiber. Because UTP is easier to configure, is less expensive, and has been widely available longer, UTP is much more common then fiber.

14. 10Base-5 uses what type of cable?a) UTPb) STPc) coaxiald) fiber

Answer: cDifficulty: MediumSection Reference: 10Base-5Explanation: Because 10Base-5 used thick coaxial cables to carry data, it was called Thick Ethernet.

16. What was the first Ethernet standard used on UTP?a) 10Base-2b) 10Base-5c) 10Base-Td) 100Base-TX

Answer: cDifficulty: EasySection Reference: 10Base-TExplanation: While 10Base-T was not the first XBase-Y standard developed, it was the first twisted-pair XBase-Y standard developed. In 1990 IEEE 802.3i formalized the 10Base-T standard. 10Base-T used CAT 3 UTP and could carry 10 mbps throughput for a distance of 100 meters. 10Base-T was a baseband technology. This standard became known as Twisted-Pair Ethernet.

18. Which Ethernet standard was developed to work over fiber?a) 10Base-2b) 10Base-5c) 100Base-TXd) 100Base-FX

Answer: dDifficulty: EasySection Reference: 100Base-FXExplanation: 100Base-FX is the version of Fast Ethernet that is intended to be used over fiber-optic cable. Introduced at the same time as 100Base-TX, 100Base-FX was part of the same IEEE 802.3y standard.

24. What is the copper version of Gigabit Ethernet?a) 1000Base-Tb) 1000Base-X

c) 1000Base-FXd) 1000Base-TX

Answer: aDifficulty: MediumSection Reference: 1000Base-TExplanation: 1000Base-T is the copper version of Gigabit Ethernet and was standardized in 1999. The standard used for copper-based Gigabit Ethernet was IEEE 802.3ab, which was designed to use CAT 5, 5e, or 6.

34. To connect to a wireless network, you would start with what?a) SSID of the wireless routerb) MAC address of the wireless routerc) password of the wireless routerd) IP address of the wireless router

Answer: aDifficulty: EasySection Reference: Install Access PointExplanation: SSID (short for Set Service Identifier) acts as the network name for a particular WAP. If you are using multiple WAPs in the same network, they will all need to have the same SSID. In Linksys WAPs, the SSID can be up to 32 characters long.

35. What helps protect data that is sent using a wireless network?a) strong authenticationb) encryptionc) RADIUSd) multiple frequencies

Answer: bDifficulty: EasySection Reference: Configure Appropriate EncryptionExplanation: Encryption is where a device such as a computer or a WAP takes the data that it is sending out and first runs an algorithm on it so that it cannot be read without first having the key to read it. This capability increases the security of a network by making it more difficult for an outsider to read what is passing across a network.

37. Which wireless mode does not use a central WAP?a) ESSIDb) ad hocc) infrastructure moded) WAP wheel

Answer: bDifficulty: MediumSection Reference: SSIDExplanation: An ad hoc wireless network is formed when a wireless network is composed of only independent wireless computers in which each device participates in forwarding wireless packets. An ad hoc wireless network has no central WAP to monitor and control it. In effect, an ad hoc wireless network is the wireless network version of a peer-to-peer network.

39. Which wireless encryption is considered the weakest?a) WEPb) WPA Personalc) WPA2 Personald) WPA2 Enterprise

Answer: aDifficulty: MediumSection Reference: Configure Appropriate EncryptionExplanation: Available encryption schemes are WPA Enterprise and Personal, WPA2 Enterprise and Personal, RADIUS, and WEP. Of these options, WEP is the weakest.

1. What communications term describes the establishment of a dedicated communications channel for the duration of a given transmission?a) circuit switchingb) packet switchingc) message switchingd) cellular switching

Answer: aDifficulty: MediumSection Reference: Circuit Switching Explanation: In its most basic definition, circuit switching is a type of communications that establishes a dedicated communications channel for the duration of a given transmission. Initially, circuit switching was done manually, where operators would perform physical connections to establish a circuit or connection. Later, this type of switching was done electronically.

3. What technology takes a voice communication, breaks the data into small packets, and sends the packets from one network segment to another?a) circuit switchingb) packet switchingc) message switchingd) cellular switching

Answer: bDifficulty: MediumSection Reference: Packet SwitchingExplanation: Packet switching opens up connections only long enough for a small data packet to move from one network segment to another. Data—regardless of type, content, or structure—is broken into small blocks called packets and sent to its destination.

5. In what type of technology is the whole message routed to its destination one hop at a time?a) circuit switchingb) packet switchingc) message switchingd) cellular switching

Answer: cDifficulty: HardSection Reference: Message SwitchingExplanation: In message switching, whole messages are routed to their destination one hop at a time. Over time, the message switching idea evolved into what we call packet switching today. With message switching, the entire message is sent out at once.

8. What type of technology does a VPN use?a) physical circuit switchingb) virtual circuit switchingc) black-box switchingd) VoIP switching

Answer: b

Difficulty: EasySection Reference: Virtual Circuit SwitchingExplanation: Virtual Private Network (VPN) is an example of a technology that makes extensive use of virtual circuit switching through the Internet.

10. Which type of cabling is the preferred media for WANs?a) fiberb) waterc) copperd) wireless

Answer: aDifficulty: EasySection Reference: Copper CablesExplanation: Phone lines still use copper in the last part of the network connections. However, today fiber optic cabling is usually used up to distribution boxes on the street and often comes directly into businesses. Fiber optic cables are now the preferred media for WAN networks.

12. What type of wireless communications is seen in WAN environments?a) fiberb) microwavec) Bluetoothd) infrared

Answer: bDifficulty: EasySection Reference: MicrowareExplanation: Microwaves are a form or wireless communications seen in WAN environments. Microwaves use the electromagnetic spectrum between the frequencies of 300 MHz and 300 GHz.

14. What is the ideal position for satellites that allow depending network connectivity?a) locked position in spaceb) geosynchronous orbitc) lunar lockedd) celestial navigated

Answer: bDifficulty: EasySection Reference: Satellite CommunicationsExplanation: The higher a satellite’s orbit, the fewer satellites are needed to be able to see every point on the earth. The ideal position to do this is something called geosynchronous orbit (GEO), also known as geostationary orbit (GSO). Satellites in this orbit will maintain their position over a set geographic position at all times.

16. What is the most common form of radio frequency WAN media?a) Bluetoothb) microwavec) satellited) cellular

Answer: dDifficulty: MediumSection Reference: Radio FrequencyExplanation: The term cellular comes from the way a cellular network functions. Each tower in a cellular network can broadcast up to a set range based on the technology used. In the case of WANs, cellular networks are the most common form of radio frequency WAN media.

18. Why do today’s cell towers use three directional antennas?a) To increase rangeb) To prevent jammingc) To prevent eavesdroppingd) To broadcast on different frequencies

Answer: aDifficulty: MediumSection Reference: Radio FrequencyExplanation: Whereas early cell networks used antennae that broadcasted in an omni-directional manner, modern cell networks do not. Directional antennae can get a longer range for the same amount of power. Nowadays, when a cell tower is being set up, it is usually equipped with three directional antennas pointed 120 degrees away from each other, allowing full coverage in a circle around the tower while pushing the tower’s range out further.

22. What refers to the entire worldwide telephone network?a) POTSb) demarcc) ATMd) PSTN

Answer: dDifficulty: EasySection Reference: Dial-upExplanation: The term Public Switched Telephone Network (PSTN) refers to the entire worldwide telephone network. PSTN uses circuit switching to establish connections between different phones. Any copper cables, fiber optic cables, microwave signals, satellite communications, or cellular networks that are used to allow any phone anywhere in the world to connect to any other phone in the world are part of the PSTN.

23. What is the point at which the network provider’s responsibility ends when connecting a site to its network?a) POTSb) demarcc) local loopd) last mile

Answer: bDifficulty: EasySection Reference: Dial-upExplanation: The location at which the PSTN service provider comes into a local home or business is called the demarc (short for demarcation ) point. The responsibility of the PSTN or other network provider’s responsibility ends here. What goes on inside the customer’s home or business is the customer’s responsibility. What happens from the demarc point outward is the service provider’s responsibility.

25. What is the first popular standard meant to replace POTS that can carry voice, video, and other services in a digital format over the PSTN?a) V.44b) ISDNc) ATMd) DSL

Answer: bDifficulty: Easy

Section Reference: ISDNExplanation: The Integrated Service Digital Network (ISDN) is a set of standards designed to carry voice, video, data, and other services in a digital format over the PSTN. Because ISDN is intended to be used over the PSTN, it uses circuit-switching technology to establish, maintain, and release connections.

26. What is the throughput of a B channel on a BRI-ISDN?a) 8 kbpsb) 16 kbpsc) 64 kbpsd) 128 kbps

Answer: cDifficulty: MediumSection Reference: ISDNExplanation: The green wire represents the D channel, which is also known as the signaling channel or control channel. The B channel has a throughput of 64 kbps.

30. What technology allows you to connect over the Internet using PSTN while talking on the phone?a) cableb) DSLc) ATMd) VoIP

Answer: bDifficulty: MediumSection Reference: DSL TechnologiesExplanation: Digital subscriber lines (DSLs) come in several variations, but all of them have some common attributes. The main common attribute is that they can use the PSTN because they use a higher frequency than voice communications to carry data. This means that line filters can be used to filter out the DSL signal for voice communications so they are not interfered with by the DSL data signal.

34. What early packet-switched network technology was originally designed for analog technology?a) X.25b) Frame Relayc) cable modemd) ATM

Answer: aDifficulty: HardSection Reference: X.25Explanation: The X.25 technology was developed in the 1970s as a means to use packet-switched communications in a WAN environment. This technology is not as widely used today because it has been replaced by newer alternatives. X.25 was originally designed as an analog technology. It also does error checking on the packets it passes through.

36. What is the speed of a T-3 line?a) 1.544 mbpsb) 4.5 mbpsc) 10.0 mbpsd) 44.7 mbps

Answer: dDifficulty: HardSection Reference: T-Lines

Explanation: T-Lines, also called T-Carriers and sometimes T-CXR, refer to a group of technologies that used various means of digital multiplexing used in telecommunications. T-3 line can carry 672 channels and 44.736 mbps data.

37. What WAN technology is based on cells that are 53 bytes in size?a) T-1b) Frame Relayc) ATMd) DSL

Answer: cDifficulty: HardSection Reference: ATMExplanation: The name Asynchronous Transfer Mode (ATM) derives from ATM using asynchronous time division multiplexing to break up communications into small frame-like segments called cells. ATM cells are a fixed size; unlike frames, which they resemble, they cannot have variable sizes. The set size of ATM cells is 5 bytes for header and an additional 48 bytes for data. Therefore, the total size of an ATM cell is 53 bytes.

40. Which of the following is used create a secure connection to a corporate network from home using the Internet as the network medium?a) VPNb) ATMc) Frame Relayd) ISDN-BRI

Answer: aDifficulty: EasySection Reference: VPNExplanation: The Virtual Private Network (VPN) technology is commonly used by corporations to allow their users to gain remote access to their corporate servers. VPN is so commonly used for this purpose because it can use the Internet to establish these connections.